This proposal requests support for study of the school-age consequences of <750 gm birthweight. A cohort of 84 <750 gm birthweight survivors from a region representing 30,000 births per year will be evaluated at 5-8 years of age. Their school-age functioning will be compared to that of 84 preterm children with birthweights 750-1499 gm and to term-born classmates; each of the comparison groups being matched on age, sex, race, and social class. Follow-up data will be gathered during 1990-1991 on growth and medical status; cognitive and neuropsychological performance; behavior, learning, and adaptive functioning; and parenting variables. Hypotheses are that: 1) <750 gm birthweight children will exhibit more negative behavior, learning, and adaptive outcomes than either of the comparison groups. These problems will be related to neurosensory disorders or mental deficiency, but also to more subtle deficits in cognitive and neuropsychological skills; 2) Parents of <750 gm birthweight children will experience more psychosocial difficulties than parents of larger very low birthweight children or of classmates; 3) Biological and environmental risk factors will have combined influences on outcome. Specifically, we anticipate that adverse outcomes will be most common in children who have experienced biologic risk, i.e., severe neonatal complications (chronic lung disease, intraventricular hemorrhage), visual deficits, and poor later growth attainment. We expect that these risks will be heightened by social disadvantage and poor parental functioning. Data will be collected from children and parents via structured interviews and questionnaires, physical examinations and standardized psychometric tests. Analysis will consist of multivariate paired comparisons of the <750 birthweight children to each comparison group, regression analyses to examine relationships between predictor variables and outcome, and application of structural equation modeling to explore links between biological and environmental risks, cognitive-neuropsychological skills, and behavior-learning-adaptive functioning. These results will enhance current knowledge of sequelae and assist us in anticipating the problems that may be associated with birth at the limits of human viability.